The present invention relates to a lifting carriage comprising a frame member, with a set of wheels provided on the frame member and arranged to enable the movement of the lifting carriage on a base, a carrying member, arranged on the frame member and extending upwardly therefrom in a direction away from said base, and a lifting member, arranged to receive an object to be lifted and displaceably provided on the carrying member, wherein the frame member comprises two side pieces connected to each other.
Such lifting carriages are previously known. According to a common concept of construction, the frame member comprises two cross-beams which connect the sidepieces and are arranged substantially in a common vertical plane which extends transversely to the normal moving direction of the lifting carriage. Therewith, the carrying member is fixed in front of the cross-beams to a side surface of these. Usually, the sidepieces comprise at their end portions the wheels by which the carriage may be driven on a floor or another base. However, known lifting carriages have the disadvantage that the length of the frame member in the moving direction tends to be so long that the flexibility and the possibilities to control the lifting carriage are reduced. It is important, when constructing such lifting carriages, that the side beams extend rearwardly from the carrying member by a given shortest length for in a sufficient safe way preventing the lifting carriage from overturning rearwardly. By reason of this safety aspect, the cross-beams located behind the carrying member will reduce the accessible space for the feet of the person which handle the lifting carriage and is to walk and push the lifting carriage in front of him at the same time, which as we know is a common working moment by such lifting carriages. That is due to the fact, that the part of the lifting carriage or the handle said person is to grip by the operation of the lifting carriage must not be positioned at a too long distance behind the carrying member, since such a construction also would lead to instability and a risk of overturning.
The object of the present invention is to provide a lifting carriage with a compact construction which make it possible to handle the lifting carriage in a flexible and safe way.
This object is obtained by the lifting carriage initially mentioned, which is characterised in that the side pieces are connected to each other by at least a first beam member on which the carrying member is arranged. By providing or putting the carrying member on the connecting beam member in this way, it is possible to avoid that essential portions of the beam member will extend rearwardly or forwardly from the carrying member and interfere with the area which is available behind and in front of the beam member, respectively. Consequently, a compact construction of the lifting carriage is enabled.
According to an embodiment of the invention, the sidepieces are also connected to each other by a second beam member which is connected to and arranged beside the carrying member in the longitudinal direction of the lifting carriage. Thereby, the second beam member is advantageously arranged at a distance from the first beam member seen in a direction perpendicular to the normal moving direction of the lifting carriage. In such a way, it is possible to arrange the second beam member as far above the first beam member and the base, that it does not interfere with the feet space for the person handling the lifting carriage. Advantageously, the second beam member is displaced rearwardly in relation to the first beam member seen in the normal moving direction of the lifting carriage.
According to another embodiment of the invention, the side pieces and said beam members are arranged in such a way that they form a space delimited in three directions, which is shaped to enable the receiving of the lifting member.
According to another embodiment of the invention, the displacement of the lifting member is provided by a driving motor arranged under the first beam member. In such a way, the location of the drive motor will not require any space which may be used, in a better way, by the lifting member or a person handling the lifting carriage. Furthermore, a screw member may be arranged to be rotated by means of the driving motor and via a nut member connected to the lifting member to transform the rotation of the screw member to a translational movement of the lifting member. Advantageously, the screw member may extend through the first beam member.
According to another embodiment of the invention, the carrying member is shaped as an elongated bar-like element. Thereby, the screw member may advantageously extend in said bar-like element. Such an elongated element may be manufactured in extruded aluminium, which guarantee a light and strength construction of the carrying member.
According to another embodiment of the invention, the sidepieces extend, at least partly, in the normal moving direction of the lifting carriage and furthermore these may extend essentially in parallel to each other.
According another embodiment of the invention, at least one of the first and second beam members is manufactured in extruded aluminium.